Classify each material as a polymer or a composite. plywood ,plastic, concrete ,fiber glass ,paper ,nylon

A polymer is a single chained molecule that is  made up of repeating subunits called monomers. In contrast, a composite is a material that is made from combining two or more molecules with similar physical or chemical properties to produce a hybrid molecule.

Plywood- it is a composite made from sticking together thin strips of wood with glue to ake stable sheets.

Plastic- a polymer made of repeating units called monomers of some kind of organic compounds.

concrete- is a composite made from mixing water cement and rocks. The mixture is not repeating and can branch in different ways which discounts it from being a polymer.

fiberglass- is a composite made that has no repeating units but made from plastic and glass fiber.

paper- is a polymer made of a repeating units of a specific monomer.

nylon- is a polymer manufactured by reacting repeating units of monomers.

Polymer:

Plastic

Paper

Nylon

Composite:

Plywood

Concrete

Fiberglass

Explanation:

The two resonating structures of Nitrous Acid are shown below. Lone pair of electrons, single and multiple bonds and non zero formal charges (red color) are also specified.

Among these two structures the structure on the left lacking formal charge is the most stable form. The instability of second resonating structure is due to the fact that it contains two formal charges (the lesser the number of formal charges the greater is the stability). Secondly in this structure one oxygen atom is having +1 formal charge. Oxygen being more electronegative feel hostile towards positive formal charge.